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1.
Mol Cell ; 83(11): 1856-1871.e9, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-37267906

RESUMEN

The pentameric FERRY Rab5 effector complex is a molecular link between mRNA and early endosomes in mRNA intracellular distribution. Here, we determine the cryo-EM structure of human FERRY. It reveals a unique clamp-like architecture that bears no resemblance to any known structure of Rab effectors. A combination of functional and mutational studies reveals that while the Fy-2 C-terminal coiled-coil acts as binding region for Fy-1/3 and Rab5, both coiled-coils and Fy-5 concur to bind mRNA. Mutations causing truncations of Fy-2 in patients with neurological disorders impair Rab5 binding or FERRY complex assembly. Thus, Fy-2 serves as a binding hub connecting all five complex subunits and mediating the binding to mRNA and early endosomes via Rab5. Our study provides mechanistic insights into long-distance mRNA transport and demonstrates that the particular architecture of FERRY is closely linked to a previously undescribed mode of RNA binding, involving coiled-coil domains.


Asunto(s)
Proteínas de Transporte Vesicular , Proteínas de Unión al GTP rab5 , Humanos , Proteínas de Transporte Vesicular/metabolismo , Proteínas de Unión al GTP rab5/genética , Proteínas de Unión al GTP rab5/análisis , Proteínas de Unión al GTP rab5/metabolismo , Endosomas/genética , Endosomas/metabolismo
2.
Mol Cell ; 83(11): 1839-1855.e13, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-37267905

RESUMEN

Localized translation is vital to polarized cells and requires precise and robust distribution of different mRNAs and ribosomes across the cell. However, the underlying molecular mechanisms are poorly understood and important players are lacking. Here, we discovered a Rab5 effector, the five-subunit endosomal Rab5 and RNA/ribosome intermediary (FERRY) complex, that recruits mRNAs and ribosomes to early endosomes through direct mRNA-interaction. FERRY displays preferential binding to certain groups of transcripts, including mRNAs encoding mitochondrial proteins. Deletion of FERRY subunits reduces the endosomal localization of transcripts in cells and has a significant impact on mRNA levels. Clinical studies show that genetic disruption of FERRY causes severe brain damage. We found that, in neurons, FERRY co-localizes with mRNA on early endosomes, and mRNA loaded FERRY-positive endosomes are in close proximity of mitochondria. FERRY thus transforms endosomes into mRNA carriers and plays a key role in regulating mRNA distribution and transport.


Asunto(s)
Endosomas , Proteínas de Unión al GTP rab5 , Proteínas de Unión al GTP rab5/genética , Proteínas de Unión al GTP rab5/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Endosomas/metabolismo , Transporte Biológico , Endocitosis/fisiología
3.
J Biol Chem ; 300(4): 107137, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38447793

RESUMEN

Experimental studies in flies, mice, and humans suggest a significant role of impaired axonal transport in the pathogenesis of Alzheimer's disease (AD). The mechanisms underlying these impairments in axonal transport, however, remain poorly understood. Here we report that the Swedish familial AD mutation causes a standstill of the amyloid precursor protein (APP) in the axons at the expense of its reduced anterograde transport. The standstill reflects the perturbed directionality of the axonal transport of APP, which spends significantly more time traveling in the retrograde direction. This ineffective movement is accompanied by an enhanced association of dynactin-1 with APP, which suggests that reduced anterograde transport of APP is the result of enhanced activation of the retrograde molecular motor dynein by dynactin-1. The impact of the Swedish mutation on axonal transport is not limited to the APP vesicles since it also reverses the directionality of a subset of early endosomes, which become enlarged and aberrantly accumulate in distal locations. In addition, it also reduces the trafficking of lysosomes due to their less effective retrograde movement. Altogether, our experiments suggest a pivotal involvement of retrograde molecular motors and transport in the mechanisms underlying impaired axonal transport in AD and reveal significantly more widespread derangement of axonal transport pathways in the pathogenesis of AD.


Asunto(s)
Enfermedad de Alzheimer , Precursor de Proteína beta-Amiloide , Transporte Axonal , Animales , Humanos , Ratones , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/patología , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Transporte Axonal/genética , Axones/metabolismo , Axones/patología , Complejo Dinactina/metabolismo , Complejo Dinactina/genética , Dineínas/metabolismo , Endosomas/metabolismo , Endosomas/genética , Lisosomas/metabolismo , Mutación , Variación Genética
4.
Circulation ; 149(2): 95-106, 2024 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-37982257

RESUMEN

BACKGROUND: Preeclampsia shares numerous risk factors with cardiovascular diseases. Here, we aimed to assess the potential utility of high-sensitivity cardiac troponin I (hs-cTnI) values during pregnancy in predicting preeclampsia occurrence. METHODS: This study measured hs-cTnI levels in 3721 blood samples of 2245 pregnant women from 4 international, prospective cohorts. Three analytical approaches were used: (1) a cross-sectional analysis of all women using a single blood sample, (2) a longitudinal analysis of hs-cTnI trajectories in women with multiple samples, and (3) analyses of prediction models incorporating hs-cTnI, maternal factors, and the sFlt-1 (soluble fms-like tyrosine kinase 1)/PlGF (placental growth factor) ratio. RESULTS: Women with hs-cTnI levels in the upper quarter had higher odds ratios for preeclampsia occurrence compared with women with levels in the lower quarter. Associations were driven by preterm preeclampsia (odds ratio, 5.78 [95% CI, 2.73-12.26]) and remained significant when using hs-cTnI as a continuous variable adjusted for confounders. Between-trimester hs-cTnI trajectories were independent of subsequent preeclampsia occurrence. A prediction model incorporating a practical hs-cTnI level of detection cutoff (≥1.9 pg/mL) alongside maternal factors provided comparable performance with the sFlt-1/PlGF ratio. A comprehensive model including sFlt-1/PlGF, maternal factors, and hs-cTnI provided added value (cross-validated area under the receiver operator characteristic, 0.78 [95% CI, 0.73-0.82]) above the sFlt-1/PlGF ratio alone (cross-validated area under the receiver operator characteristic, 0.70 [95% CI, 0.65-0.76]; P=0.027). As assessed by likelihood ratio tests, the addition of hs-cTnI to each prediction model significantly improved the respective prediction model not incorporating hs-cTnI, particularly for preterm preeclampsia. Net reclassification improvement analyses indicated that incorporating hs-cTnI improved risk prediction predominantly by correctly reclassifying women with subsequent preeclampsia occurrence. CONCLUSIONS: These exploratory findings uncover a potential role for hs-cTnI as a complementary biomarker in the prediction of preeclampsia. After validation in prospective studies, hs-cTnI, alongside maternal factors, may either be considered as a substitute for angiogenic biomarkers in health care systems where they are sparce or unavailable, or as an enhancement to established prediction models using angiogenic markers.


Asunto(s)
Preeclampsia , Recién Nacido , Embarazo , Femenino , Humanos , Factor de Crecimiento Placentario , Preeclampsia/diagnóstico , Estudios Prospectivos , Troponina I , Estudios Transversales , Receptor 1 de Factores de Crecimiento Endotelial Vascular , Biomarcadores
5.
PLoS Pathog ; 19(8): e1011583, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37651385

RESUMEN

Fungal infections are rising, with over 1.5 billion cases and more than 1 million deaths recorded each year. Among these, Candida infections are frequent in at-risk populations and the rapid development of drug resistance and tolerance contributes to their clinical persistence. Few antifungal drugs are available, and their efficacy is declining due to the environmental overuse and the expansion of multidrug-resistant species. One way to prolong their utility is by applying them in combination therapy. Here, we highlight recently described azole potentiators belonging to different categories: natural, repurposed, or novel compounds. We showcase examples of molecules and discuss their identified or proposed mode of action. We also emphasise the challenges in azole potentiator development, compounded by the lack of animal testing, the overreliance on Candida albicans and Candida auris, as well as the limited understanding of compound efficacy.


Asunto(s)
Candida , Candidiasis , Animales , Candida albicans , Candidiasis/tratamiento farmacológico , Antifúngicos/farmacología , Azoles/farmacología
6.
Radiology ; 310(3): e231429, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38530172

RESUMEN

Background Differentiating between benign and malignant vertebral fractures poses diagnostic challenges. Purpose To investigate the reliability of CT-based deep learning models to differentiate between benign and malignant vertebral fractures. Materials and Methods CT scans acquired in patients with benign or malignant vertebral fractures from June 2005 to December 2022 at two university hospitals were retrospectively identified based on a composite reference standard that included histopathologic and radiologic information. An internal test set was randomly selected, and an external test set was obtained from an additional hospital. Models used a three-dimensional U-Net encoder-classifier architecture and applied data augmentation during training. Performance was evaluated using the area under the receiver operating characteristic curve (AUC) and compared with that of two residents and one fellowship-trained radiologist using the DeLong test. Results The training set included 381 patients (mean age, 69.9 years ± 11.4 [SD]; 193 male) with 1307 vertebrae (378 benign fractures, 447 malignant fractures, 482 malignant lesions). Internal and external test sets included 86 (mean age, 66.9 years ± 12; 45 male) and 65 (mean age, 68.8 years ± 12.5; 39 female) patients, respectively. The better-performing model of two training approaches achieved AUCs of 0.85 (95% CI: 0.77, 0.92) in the internal and 0.75 (95% CI: 0.64, 0.85) in the external test sets. Including an uncertainty category further improved performance to AUCs of 0.91 (95% CI: 0.83, 0.97) in the internal test set and 0.76 (95% CI: 0.64, 0.88) in the external test set. The AUC values of residents were lower than that of the best-performing model in the internal test set (AUC, 0.69 [95% CI: 0.59, 0.78] and 0.71 [95% CI: 0.61, 0.80]) and external test set (AUC, 0.70 [95% CI: 0.58, 0.80] and 0.71 [95% CI: 0.60, 0.82]), with significant differences only for the internal test set (P < .001). The AUCs of the fellowship-trained radiologist were similar to those of the best-performing model (internal test set, 0.86 [95% CI: 0.78, 0.93; P = .39]; external test set, 0.71 [95% CI: 0.60, 0.82; P = .46]). Conclusion Developed models showed a high discriminatory power to differentiate between benign and malignant vertebral fractures, surpassing or matching the performance of radiology residents and matching that of a fellowship-trained radiologist. © RSNA, 2024 See also the editorial by Booz and D'Angelo in this issue.


Asunto(s)
Aprendizaje Profundo , Fracturas de la Columna Vertebral , Humanos , Femenino , Masculino , Anciano , Reproducibilidad de los Resultados , Estudios Retrospectivos , Fracturas de la Columna Vertebral/diagnóstico por imagen , Tomografía Computarizada Multidetector , Hospitales Universitarios
7.
Am J Pathol ; 193(2): 161-181, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36410420

RESUMEN

The roof plate-specific spondin-leucine-rich repeat-containing G-protein coupled receptor 4/5 (LGR4/5)-zinc and ring finger 3 (ZNRF3)/ring finger protein 43 (RNF43) module is a master regulator of hepatic Wnt/ß-catenin signaling and metabolic zonation. However, its impact on nonalcoholic fatty liver disease (NAFLD) remains unclear. The current study investigated whether hepatic epithelial cell-specific loss of the Wnt/ß-catenin modulator Lgr4/5 promoted NAFLD. The 3- and 6-month-old mice with hepatic epithelial cell-specific deletion of both receptors Lgr4/5 (Lgr4/5dLKO) were compared with control mice fed with normal diet (ND) or high-fat diet (HFD). Six-month-old HFD-fed Lgr4/5dLKO mice developed hepatic steatosis and fibrosis but the control mice did not. Serum cholesterol-high-density lipoprotein and total cholesterol levels in 3- and 6-month-old HFD-fed Lgr4/5dLKO mice were decreased compared with those in control mice. An ex vivo primary hepatocyte culture assay and a comprehensive bile acid (BA) characterization in liver, plasma, bile, and feces demonstrated that ND-fed Lgr4/5dLKO mice had impaired BA secretion, predisposing them to develop cholestatic characteristics. Lipidome and RNA-sequencing analyses demonstrated severe alterations in several lipid species and pathways controlling lipid metabolism in the livers of Lgr4/5dLKO mice. In conclusion, loss of hepatic Wnt/ß-catenin activity by Lgr4/5 deletion led to loss of BA secretion, cholestatic features, altered lipid homeostasis, and deregulation of lipoprotein pathways. Both BA and intrinsic lipid alterations contributed to the onset of NAFLD.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Animales , Ratones , Enfermedad del Hígado Graso no Alcohólico/metabolismo , beta Catenina/metabolismo , Leucina/metabolismo , Hígado/metabolismo , Colesterol/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Ratones Endogámicos C57BL , Dieta Alta en Grasa/efectos adversos
8.
HIV Med ; 25(1): 117-128, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37771207

RESUMEN

OBJECTIVES: Our objective was to obtain long-term data on the incidence of sexually transmitted infections (STIs) and their association with behavioural factors after widespread pre-exposure prophylaxis (PrEP) implementation. METHODS: This was a time-to-event analysis of a national PrEP cohort in Switzerland (SwissPrEPared study). Participants were people without HIV interested in taking PrEP with at least two STI screening visits. Primary outcomes were incidence rate of gonorrhoea, chlamydia, and syphilis. The association between behavioural factors and STI diagnosis was expressed using hazard ratios. We adjusted for testing frequency and calendar year. RESULTS: This analysis included 3907 participants enrolled between April 2019 and April 2022, yielding 3815.7 person-years of follow-up for gonorrhoea (15 134 screenings), 3802.5 for chlamydia (15 141 screenings), and 3858.6 for syphilis (15 001 screenings). The median age was 39 years (interquartile range [IQR] 32-47), 93.8% (n = 3664) identified as men who have sex with men (MSM). The incidence was 22.8 (95% confidence interval [CI] 21.3-24.4) per 100 person-years for gonorrhoea, 26.3 (95% CI 24.7-28.0) for chlamydia, and 4.4 (95% CI 3.8-5.1) for syphilis. Yearly incidence rates decreased between 2019 (all bacterial STIs: 81.6; 95% CI 59.1-109.9) and 2022 (all bacterial STIs: 49.8; 95% CI 44.6-55.3). Participants reporting chemsex substance use were at higher risk of incident STIs, as were those reporting multiple sexual partners. Younger age was associated with a higher risk of gonorrhoea and chlamydia. CONCLUSIONS: Incidence rates of bacterial STIs decreased over time. Young MSM, those with multiple partners, and those using chemsex substances were at increased risk of STIs.


Asunto(s)
Gonorrea , Infecciones por VIH , Profilaxis Pre-Exposición , Minorías Sexuales y de Género , Enfermedades Bacterianas de Transmisión Sexual , Enfermedades de Transmisión Sexual , Sífilis , Masculino , Humanos , Adulto , Incidencia , Homosexualidad Masculina , Sífilis/epidemiología , Gonorrea/epidemiología , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Enfermedades de Transmisión Sexual/epidemiología , Enfermedades de Transmisión Sexual/prevención & control , Enfermedades Bacterianas de Transmisión Sexual/epidemiología
9.
Ann Neurol ; 94(6): 1080-1085, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37753809

RESUMEN

The minor allele of the genetic variant rs10191329 in the DYSF-ZNF638 locus is associated with unfavorable long-term clinical outcomes in multiple sclerosis patients. We investigated if rs10191329 is associated with brain atrophy measured by magnetic resonance imaging in a discovery cohort of 748 and a replication cohort of 360 people with relapsing multiple sclerosis. We observed an association with 28% more brain atrophy per rs10191329*A allele. Our results encourage stratification for rs10191329 in clinical trials. Unraveling the underlying mechanisms may enhance our understanding of pathophysiology and identify treatment targets. ANN NEUROL 2023;94:1080-1085.


Asunto(s)
Enfermedades del Sistema Nervioso Central , Esclerosis Múltiple , Enfermedades Neurodegenerativas , Humanos , Esclerosis Múltiple/diagnóstico por imagen , Esclerosis Múltiple/genética , Esclerosis Múltiple/patología , Encéfalo/patología , Imagen por Resonancia Magnética/métodos , Enfermedades Neurodegenerativas/patología , Atrofia/patología
10.
Osteoporos Int ; 35(6): 951-969, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38300316

RESUMEN

Fracture liaison services (FLS) have been proven clinically effective and cost-effective in preventing subsequent fractures among patients with an existing fragility fracture. Little is known about their monetary benefits such as their return on investment (ROI). This systematic review aimed to investigate the ROI of FLS and identify the FLS characteristics with better ROI. Studies on the cost-effectiveness of FLS published between January 2000 and December 2022 were searched from MEDLINE, EMBASE, PubMed, and Cochrane Central. Two independent reviewers conducted study selection and data extraction. ROI was calculated based on the difference between monetary benefits and FLS costs divided by the FLS costs. Subgroup analysis of ROI was performed across FLS types and FLS design details. A total of 23 FLS were included in this review. The majority of them were targeting patients aged over 50 years having fractures without identified sites. The mean ROI of these FLS was 10.49 (with a median ROI of 7.57), and 86.96% of FLS had positive ROI. FLS making treatment recommendations yielded the highest ROI (with a mean ROI of 18.39 and a median of 13.60). Incorporating primary care providers (with a mean ROI of 16.04 and a median of 13.20) or having them as program leaders (with a mean ROI of 12.07 and a median of 12.07) has demonstrated a high ROI. FLS for specific fracture sites had great monetary return. Intensive FLS such as type A and B FLS programs had higher ROI than non-intensive type C and D FLS. This review revealed a 10.49-fold monetary return of FLS. Identified characteristics contributing to greater economic return informed value-for-money FLS designs. Findings highlight the importance of FLS and the feasibility of expanding their contribution in mitigating the economic burden of osteoporotic fracture and are conducive to the promotion of FLS internationally.


Asunto(s)
Análisis Costo-Beneficio , Fracturas Osteoporóticas , Humanos , Fracturas Osteoporóticas/prevención & control , Fracturas Osteoporóticas/economía , Costos de la Atención en Salud/estadística & datos numéricos , Prevención Secundaria/organización & administración , Prevención Secundaria/economía
11.
J Magn Reson Imaging ; 59(5): 1542-1552, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-37501387

RESUMEN

BACKGROUND: Several magnetic resonance (MR) techniques have been suggested for radiation-free imaging of osseous structures. PURPOSE: To compare the diagnostic value of ultra-short echo time and gradient echo T1-weighted MRI for the assessment of vertebral pathologies using histology and computed tomography (CT) as the reference standard. STUDY TYPE: Prospective. SUBJECTS: Fifty-nine lumbar vertebral bodies harvested from 20 human cadavers (donor age 73 ± 13 years; 9 male). FIELD STRENGTH/SEQUENCE: Ultra-short echo time sequence optimized for both bone (UTEb) and cartilage (UTEc) imaging and 3D T1-weighted gradient-echo sequence (T1GRE) at 3 T; susceptibility-weighted imaging (SWI) gradient echo sequence at 1.5 T. CT was performed on a dual-layer dual-energy CT scanner using a routine clinical protocol. ASSESSMENT: Histopathology and conventional CT were acquired as standard of reference. Semi-quantitative and quantitative morphological features of degenerative changes of the spines were evaluated by four radiologists independently on CT and MR images independently and blinded to all other information. Features assessed were osteophytes, endplate sclerosis, visualization of cartilaginous endplate, facet joint degeneration, presence of Schmorl's nodes, and vertebral dimensions. Vertebral disorders were assessed by a pathologist on histology. STATISTICAL TESTS: Agreement between T1GRE, SWI, UTEc, and UTEb sequences and CT imaging and histology as standard of reference were assessed using Fleiss' κ and intra-class correlation coefficients, respectively. RESULTS: For the morphological assessment of osteophytes and endplate sclerosis, the overall agreement between SWI, T1GRE, UTEb, and UTEc with the reference standard (histology combined with CT) was moderate to almost perfect for all readers (osteophytes: SWI, κ range: 0.68-0.76; T1GRE: 0.92-1.00; UTEb: 0.92-1.00; UTEc: 0.77-0.85; sclerosis: SWI, κ range: 0.60-0.70; T1GRE: 0.77-0.82; UTEb: 0.81-0.92; UTEc: 0.61-0.71). For the visualization of the cartilaginous endplate, UTEc showed the overall best agreement with the reference standard (histology) for all readers (κ range: 0.85-0.93). DATA CONCLUSIONS: Morphological assessment of vertebral pathologies was feasible and accurate using the MR-based bone imaging sequences compared to CT and histopathology. T1GRE showed the overall best performance for osseous changes and UTEc for the visualization of the cartilaginous endplate. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: Stage 2.


Asunto(s)
Osteofito , Humanos , Masculino , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Estudios Prospectivos , Esclerosis , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X/métodos , Vértebras Lumbares/diagnóstico por imagen , Estándares de Referencia
12.
Exp Physiol ; 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39014554

RESUMEN

While it is well-established that a period of interval training performed at near maximal effort, such as speed endurance training (SET), enhances intense exercise performance in well-trained individuals, less is known about its effect on cardiac morphology and function as well as blood volume. To investigate this, we subjected 12 Under-20 Danish national team ice hockey players (age 18 ± 1 years, mean ± SD) to 4 weeks of SET, consisting of 6-10 × 20 s skating bouts at maximal effort interspersed by 2 min of recovery conducted three times weekly. This was followed by 4 weeks of regular training (follow-up). We assessed resting cardiac function and dimensions using transthoracic echocardiography and quantified total blood volume with the carbon monoxide rebreathing technique at three time points: before SET, after SET and after the follow-up period. After SET, stroke volume had increased by 10 (2-18) mL (mean (95% CI)), left atrial end-diastolic volume by 10 (3-17) mL, and circumferential strain improved by 0.9%-points (1.7-0.1) (all P < 0.05). At follow-up, circumferential strain and left atrial end-diastolic volume were reverted to baseline levels, while stroke volume remained elevated. Blood volume and morphological parameters for the left ventricle, including mass and end-diastolic volume, did not change during the study. In conclusion, our findings demonstrate that a brief period of SET elicits beneficial central cardiac adaptations in elite ice hockey players independent of changes in blood volume.

13.
J Exp Biol ; 227(5)2024 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-38323432

RESUMEN

Metabolic physiology and animal behaviour are often considered to be linked, positively or negatively, according to either the performance or allocation models. Performance seems to predominate over allocation in natural systems, but the constraining environmental context may reveal allocation limitations to energetically expensive behaviours. Habitat disturbance, such as the large-scale fire that burnt wetlands of Biebrza National Park (NE Poland), degrades natural ecosystems. It arguably reduces food and shelter availability, modifies predator-prey interactions, and poses a direct threat for animal survival, such as that of the wetland specialist root vole Microtus oeconomus. We hypothesized that fire disturbance induces physiology-behaviour co-expression, as a consequence of changed environmental context. We repeatedly measured maintenance and exercise metabolism, and behavioural responses to the open field, in a root voles from post-fire and unburnt locations. Highly repeatable maintenance metabolism and distance moved during behavioural tests correlated positively, but relatively labile exercise metabolism did not covary with behaviour. At the same time, voles from a post-fire habitat had higher maintenance metabolism and moved shorter distances than voles from unburnt areas. We conclude there is a prevalence of the performance mechanism, but simultaneous manifestation of context-dependent allocation constraints of the physiology-behaviour covariation after disturbance. The last occurs at the within-individual level, indicating the significance of behavioural plasticity in the context of environmental disturbance.


Asunto(s)
Ecosistema , Incendios , Animales , Conducta Animal/fisiología , Arvicolinae
14.
Eur Radiol ; 34(10): 6796-6804, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38662099

RESUMEN

OBJECTIVES: Basilar artery occlusion (BAO) may be etiologically attributed to embolism or in situ thrombosis due to basilar stenosis (BS). Patients with BAO due to BS (BAOS) are known to have worse outcomes than patients with embolic occlusions (BAOE). BAOS occurs more proximally in the basilar artery (BA) than BAOE. We hypothesize that differing brain stem infarct patterns contribute to outcome differences between these stroke etiologies. METHODS: This retrospective study includes 199 consecutive patients with BAO who received endovascular treatment at a single center. Final infarction in brain parenchyma dependent on the posterior circulation was graded semiquantitatively on magnetic resonance imaging (MRI). Associations to underlying stenosis and angiographic and clinical outcome variables were tested. The primary endpoint was early good clinical outcome (EGCO, mRS score ≤ 3 at discharge). RESULTS: Infarct extension of the medulla oblongata (OR = 0.25; 95% CI = 0.07-0.86; p = 0.03), the inferior pons (OR = 0.328; 95% CI = 0.17-0.63; p = 0.001), the superior pons (OR = 0.57; 95% CI = 0.33-0.99; p = 0.046), and the occipital lobes (OR = 0.46; 95% CI = 0.26-0.80; p = 0.006) negatively predicted EGCO. Infarct extension for other posterior-circulation-dependent brain regions was not independently associated with unfavorable early outcomes. Patients with BAOS had more proximal occlusions and greater infarct volumes in the inferior brain stem. Successful reperfusion (mTICI 2b-3) occurred more often in patients with BAOE than in BAOS (BAOE: 131 (96.3%); BAOS: 47 (83.9%), p = 0.005). CONCLUSION: Unfavorable early outcomes in patients with BAOS may be explained by a higher likelihood of inferior brain stem infarcts and lower rates of reperfusion success. CLINICAL RELEVANCE STATEMENT: Basilar artery occlusion due to underlying stenosis is associated with a poorer prognosis than that caused by embolism; these results suggest that aggressive endovascular therapy, usually involving the placement of a permanent stent, may be warranted in these patients. KEY POINTS: Inferior brain stem and occipital infarcts are prognostically unfavorable in basilar artery occlusion. Basilar artery occlusion due to stenosis occurs more proximally and is associated with worse outcomes. Differentiating etiologies of basilar artery occlusion may influence how aggressively treated the occlusion is.


Asunto(s)
Accidente Cerebrovascular Isquémico , Insuficiencia Vertebrobasilar , Humanos , Masculino , Femenino , Estudios Retrospectivos , Anciano , Persona de Mediana Edad , Resultado del Tratamiento , Insuficiencia Vertebrobasilar/diagnóstico por imagen , Insuficiencia Vertebrobasilar/complicaciones , Accidente Cerebrovascular Isquémico/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Procedimientos Endovasculares/métodos , Arteria Basilar/diagnóstico por imagen , Anciano de 80 o más Años
15.
AIDS Care ; 36(4): 442-451, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37182220

RESUMEN

To prevent hepatitis C virus (HCV) reinfection, within the Swiss HCVree Trial, a preventive risk reduction intervention was implemented alongside curative treatment. Formative qualitative research identified three response patterns to the intervention. This mixed-methods study's aim was to cross-validate group differences in (a) the content of sexual risk reduction goals set during intervention and (b) the extent of their behavioural change in condomless anal intercourse with non-steady partners (nsCAI), sexualised and intravenous drug use at start and six-month post-intervention. Qualitative thematic analysis was used to summarise goal setting domains. Quantitative descriptive analysis was used to evaluate group differences based on assumptions of the group descriptions. Results largely confirmed assumptions on inter-group response differences in goal setting and behaviour: as expected group 1 Avoid risks showed the lowest HCV risk profile with changes in nsCAI. Group 2 Minimize-risks and Group 3 Accept-risks showed unchanged nsCAI. Group 3 had the highest HCV risk profile. Differences in their goal preferences (1: condom use; 2 reduction blood exposure; 3 safer dating) highlight diversity in attitudes to behavioural change. Our results improve understanding of variability in intervention responses such as changes in attitudes and behaviour. This provides evidence for intervention tailoring and outcome measurement.


Asunto(s)
Infecciones por VIH , Hepatitis C , Masculino , Humanos , Hepacivirus , Infecciones por VIH/prevención & control , Homosexualidad Masculina , Reinfección , Conducta Sexual , Hepatitis C/prevención & control , Conducta de Reducción del Riesgo
16.
BMC Neurol ; 24(1): 326, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39242510

RESUMEN

BACKGROUND: Mirror movements (MM) are commonly caused by a defect of interhemispheric pathways also affected in multiple sclerosis (MS), particularly the corpus callosum. We investigated the prevalence of MM in MS in relation to functional and morphological callosal fiber integrity by transcranial magnetic stimulation (TMS), magnetic resonance imaging (MRI), as well as fatigue. METHODS: In 21 patients with relapsing-remitting MS and 19 healthy controls, MM were assessed and graded (Woods and Teuber scale: MM 1-4) using a bedside test. Fatigue was evaluated using the Fatigue Scale for Motor and Cognitive Functions (FSMC) questionnaire. TMS measured ipsilateral silent period latency and duration. MRI assessed callosal atrophy by measuring the normalized corpus callosum area (nCCA), corpus callosum index (CCI), and lesion volume. RESULTS: MS patients had significantly more often and pronounced MM compared to healthy controls (p = 0.0002) and nCCA was significantly lower (p = 0.045) in MRI studies. Patients with higher MM scores (MM > 1 vs. MM 0/1) showed significantly more fatigue (higher FSMC sum score, p = 0.04, motor score, p = 0.01). In TMS and MRI studies, no significant differences were found between patients with MM 0/1 and those with MM > 1 (ipsilateral silent period measurements, CCA, CCI and lesion volume). CONCLUSIONS: MM are common in MS and can easily be detected through bedside testing. As MM are associated with fatigue, they might indicate fatigue in MS. It is possible that other cerebral structures, in addition to the corpus callosum, may contribute to the origin of MM in MS.


Asunto(s)
Cuerpo Calloso , Imagen por Resonancia Magnética , Estimulación Magnética Transcraneal , Humanos , Femenino , Masculino , Adulto , Cuerpo Calloso/diagnóstico por imagen , Cuerpo Calloso/patología , Estimulación Magnética Transcraneal/métodos , Imagen por Resonancia Magnética/métodos , Persona de Mediana Edad , Esclerosis Múltiple Recurrente-Remitente/diagnóstico por imagen , Esclerosis Múltiple Recurrente-Remitente/fisiopatología , Esclerosis Múltiple Recurrente-Remitente/complicaciones , Esclerosis Múltiple/diagnóstico por imagen , Esclerosis Múltiple/fisiopatología , Esclerosis Múltiple/complicaciones , Esclerosis Múltiple/patología , Fatiga/diagnóstico por imagen , Fatiga/fisiopatología , Fatiga/etiología , Fatiga/epidemiología
17.
J Pediatr Gastroenterol Nutr ; 79(2): 343-351, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38938000

RESUMEN

OBJECTIVES: The aim of our study was to assess the impact of the very early introduction of refeeding on the course of acute pancreatitis (AP) in children. Additionally, we evaluated the effect of nutrition on inflammatory markers, including cytokines. METHODS: This prospective randomised study was conducted in three university hospitals in Poland. Patients, aged 1-18 years with AP, were randomised into two groups: A-refeeding within 24 h of hospital admission (very early), and B-refeeding at least 24 h after admission (early nutrition). The severity of AP was assessed after 48 h. The serum concentrations of four cytokines (tumour necrosis factor α [TNFα], interleukin-1ß [IL-1ß], interleukin-6 [IL-6] and interleukin-8 [IL-8]) and C-reactive protein, as well as the activity of amylase, lipase and aminotransferases, were measured during the first 3 days of hospitalisation. RESULTS: A total of 94 children were recruited to participate in the study. The statistical analysis included 75 patients with mild pancreatitis: 42-group A and 33-group B. The two groups did not differ in the length of hospitalisation (p = 0.22), AP symptoms or results of laboratory tests. Analysis of cytokine levels was conducted for 64 children: 38-group A and 26-group B. We did not find a difference in concentrations of the measured cytokines, except for IL-1ß on the third day of hospitalisation (p = 0.01). CONCLUSIONS: The time of initiation of oral nutrition within 24 h (very early) or after 24 h (early) from the beginning of hospitalisation had no impact on the length of hospitalisation, concentrations of TNF-α, IL-1ß, IL-6 and IL-8, activity of amylase and lipase or occurrence of symptoms in children with mild AP.


Asunto(s)
Citocinas , Pancreatitis , Humanos , Pancreatitis/sangre , Masculino , Femenino , Niño , Preescolar , Estudios Prospectivos , Adolescente , Lactante , Citocinas/sangre , Proteína C-Reactiva/análisis , Proteína C-Reactiva/metabolismo , Polonia , Índice de Severidad de la Enfermedad , Biomarcadores/sangre , Lipasa/sangre , Enfermedad Aguda
18.
Dig Dis Sci ; 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39160386

RESUMEN

BACKGROUND AND AIMS: Primary sclerosing cholangitis (PSC) is a chronic inflammatory liver disorder without effective medical treatment which is characterized by inflammation and fibrotic structures around the bile ducts. Biliary epithelial cells (cholangiocytes) are the target and potential disease drivers in PSC, yet little is known if cholangiocytes from PSC patients differ from non-PSC controls. To characterize cholangiocytes at early rather than end-stage disease, cholangiocyte organoids (COs) were derived from diseased bile ducts of PSC patients and compared to organoids generated from disease controls. METHODS: Cholangiocytes were obtained during endoscopic retrograde cholangiopancreatography (ERCP) brushing of diseased bile duct areas and expanded as organoids using previously established culture methods. Stable CO lines were analyzed for cell type identity, basic cholangiocyte function, and transcriptomic signature. RESULTS: We demonstrate that cholangiocytes, derived from the damaged area within the bile ducts of PSC patients, can be expanded in culture without displaying functional or genetic disease-related features. We further show that COs from patients who later were diagnosed with dysplasia exhibit higher expression of the cancer-associated genes PGC, FXYD2, MIR4435-2HG, and HES1. CONCLUSIONS: Our results demonstrate that PSC organoids are largely similar to control organoids after culture and highlight the significance of COs as a tool for regenerative medicine approaches as well as their potential for discovering new potential biomarkers for diagnosing cholangiocarcinoma.

19.
BMC Med Imaging ; 24(1): 43, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38350900

RESUMEN

BACKGROUND: A deep learning (DL) model that automatically detects cardiac pathologies on cardiac MRI may help streamline the diagnostic workflow. To develop a DL model to detect cardiac pathologies on cardiac MRI T1-mapping and late gadolinium phase sensitive inversion recovery (PSIR) sequences were used. METHODS: Subjects in this study were either diagnosed with cardiac pathology (n = 137) including acute and chronic myocardial infarction, myocarditis, dilated cardiomyopathy, and hypertrophic cardiomyopathy or classified as normal (n = 63). Cardiac MR imaging included T1-mapping and PSIR sequences. Subjects were split 65/15/20% for training, validation, and hold-out testing. The DL models were based on an ImageNet pretrained DenseNet-161 and implemented using PyTorch and fastai. Data augmentation with random rotation and mixup was applied. Categorical cross entropy was used as the loss function with a cyclic learning rate (1e-3). DL models for both sequences were developed separately using similar training parameters. The final model was chosen based on its performance on the validation set. Gradient-weighted class activation maps (Grad-CAMs) visualized the decision-making process of the DL model. RESULTS: The DL model achieved a sensitivity, specificity, and accuracy of 100%, 38%, and 88% on PSIR images and 78%, 54%, and 70% on T1-mapping images. Grad-CAMs demonstrated that the DL model focused its attention on myocardium and cardiac pathology when evaluating MR images. CONCLUSIONS: The developed DL models were able to reliably detect cardiac pathologies on cardiac MR images. The diagnostic performance of T1 mapping alone is particularly of note since it does not require a contrast agent and can be acquired quickly.


Asunto(s)
Aprendizaje Profundo , Gadolinio , Humanos , Imagen por Resonancia Magnética/métodos , Miocardio/patología , Medios de Contraste , Pericardio
20.
Scand J Med Sci Sports ; 34(1): e14500, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37880916

RESUMEN

PURPOSE: Many athletes use long-acting beta2 -agonist formoterol in treatment of asthma. However, studies in non-athlete cohorts demonstrate that inhaled formoterol can enhance sprint performance calling into question whether its use in competitive sports should be restricted. We investigated whether formoterol at upper recommended inhaled doses (54 µg) would enhance sprint ability and intense exercise performance in elite cyclists. METHODS: Twenty-one male cyclists (V̇O2max : 70.4 ± 4.3 mL × min-1 × kg-1 , mean ± SD) completed two 6-s all-out sprints followed by 4-min all-out cycling after inhaling either 54 µg formoterol or placebo. We also assessed cyclists' leg muscle mass by dual-energy X-ray absorptiometry and muscle fiber type distribution of vastus lateralis biopsies. RESULTS: Peak and mean power output during the 6-s sprint was 32 W (95% CI, 19-44 W, p < 0.001) and 36 W (95% CI, 24-48 W, p < 0.001) higher with formoterol than placebo, corresponding to an enhancing effect of around 3%. Power output during 4-min all-out cycling was 9 W (95% CI, 2-16 W, p = 0.01) greater with formoterol than placebo, corresponding to an enhancing effect of 2.3%. Performance changes in response to formoterol were unrelated to cyclists' VO2max and leg lean mass, whereas muscle fiber Type I distribution correlated with change in sprinting peak power in response to formoterol (r2 = 0.314, p = 0.012). CONCLUSION: Our findings demonstrate that an inhaled one-off dose of 54 µg formoterol has a performance-enhancing potential on sprint ability and short intense performance in elite male cyclists, which is irrespective of training status but partly related to muscle fiber type distribution for sprint ability.


Asunto(s)
Asma , Rendimiento Atlético , Humanos , Masculino , Fumarato de Formoterol/farmacología , Músculo Esquelético , Ejercicio Físico , Músculo Cuádriceps/fisiología , Ciclismo/fisiología , Rendimiento Atlético/fisiología
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